Portable speaker



FIG. 1 is a top, front and right side perspective view of a portable speaker, embodying our new design;

FIG. 2 is a front elevation view thereof;

FIG. 3 is a rear elevation view thereof;

FIG. 4 is a left side elevation view thereof;

FIG. 5 is a right side elevation view thereof;

FIG. 6 is a top plan view thereof; and,

FIG. 7 is a bottom plan view thereof.

The broken lines shown are included for the purpose of illustrating portions of the portable speaker that form no part of the claim. 

CLAIM The ornamental design for a portable speaker, as shown and described. 